The schema goes only as far as built-in properties
There's no need to map the rest as they will not be used in any way by the diagram.
The approach in the http://dojo.telerik.com/osOmA/6 snippet is what we'd recommend too.
New items are added directly through the data source.
The visual template is the same for all shapes and can call sub-templates based on data item fields.
Mixing addShape (unbound mode) with dataSource.add is not recommended.
When bound to a data source the widget expects all changes to channel through it.
I hope this helps.
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